In the prior art, a microcomputer has been arranged for performing bit manipulations, such as clearing a selected bit or setting a selected bit in a word. Additionally by way of example, a bit can be moved from any bit position in a source word to any bit position in a destination word.
During the move bit operation, the arithmetic logic unit performs a test on the selected bit in the source word. This test procedure includes the generation of a test mask before performing the test. Depending upon the outcome of the test, a selected bit position in the destination either will be cleared or set. Other bits in the destination remain unchanged. This move bit operation requires two or more instructions and therefore two or more instruction intervals to move a single bit.
Thus when a programmer desires to move a bit during a single instruction interval, a problem arises because plural instructions are used for completing the move. Moving a bit in a single instruction interval is a valuable feature for a microcomputer designed into a control arrangement that performs many bit manipulation operations.